High Time

Unless We Act Soon And In A Big Way, Disaster, Say The Experts, Will Come Flooding In Through Our Front Door

From a distance, it could be any pleasure craft, plying the sun-dappled waters south of McCormick Place. Sharp eyes are needed to see the trail of bubbles moving steadily across the surface away from the small white power cruiser towards the shore. The bubble trail stops advancing at a point about 3 feet from the rocks at the foot of 31st Street. For a few minutes bubbles continue to roil up from the same spot, as if an offshore oil strike is about to come in. Then suddenly the surface is broken by a head swathed in black skulltight rubber.

FOR THE RECORD - Additional material published Oct. 11, 1987:Corrections and clarifications.A Lake Forest house pictured in the SUNDAY, Magazine of the Oct. 4 Tribune was incorrectly identified as the Byron Smith home. It does not belong to either Solomon Byron Smith or Edward Byron Smith. The Tribune regrets the error.

Standing in the stern of the boat, Luke Cosme manages to look chagrined and triumphant at the same time. ``I knew it,`` exclaims Cosme, who, after 52 years as an engineer with the Chicago Park District, probably knows more about the vicissitudes of Chicago`s shoreline than any other living person.

Cosme`s purpose this late summer morning is to conduct an underwater survey of the ``edge``-that critical strip of real estate where Chicago and the lake collide and where the aging, 26-mile bulwark of rock, wood, steel and sand is barely able to protect the land from the water`s ravages. The bulwark has been sorely tested in recent months. Already seriously weakened by dry rot, erosion and time, it has been swamped by precipitously rising lake levels, levels that peaked last autumn with record highs. Then, after a wave- tossed December and January, came the coup de grace: a wicked storm last Feb. 8 that sent huge whitecaps slamming murderously into the bulwark, damaging it in a number of strategic places and causing widespread flooding and other mischief to buildings and roadways beyond.

One of the primary trouble spots is at 31st Street, where the shoreline, as it is along much of Chicago`s lakefront, is shielded by what is called a stepped-stone revetment, that familiar tiered arrangement of cut limestone rocks that leads gradually down to the water like a set of giant stairs. But the revetment at 31st Street is in partial ruin, suggesting the grandstand of some ancient amphitheater. Rocks are missing; others rest at crazy angles, their rusted reinforcing rods exposed and twisted like spaghetti.

Kleist has discovered the reason: a blowout below the waterline, where the revetment is supported by a line of tightly packed wooden pilings sunk deep into the sandy lake bottom. A blowout occurs when deflected wave action eats away at the sand and the pilings slip out of their sockets like teeth in bad gums, causing the revetment to slump into the water.

``That will have to be fixed,`` says Cosme, who later this morning will find a similar blowout at 38th Street, and an underwater cavern, big enough to house an adult, that waves had gouged out below the pedestrian walkway at 51st Street, making it a threat to life and limb. He looks protectively at the elevated dirt berm that runs for 300 yards or so behind the revetment at 31st. A kind of levee, the berm was put in by the park district last spring to prevent a recurrence of the severe flooding of South Lake Shore Drive that accompanied the February storm. ``If we don`t do something,`` says Cosme,

``mark my words, one more big storm, and the berm will be history and the water will be back on Lake Shore Drive.``

Chicago`s shoreline is desperately ill. In many ways its troubles mirror those of the entire Illinois shore, from Winthrop Harbor on the north to Calumet Beach on the south. Everywhere, the land is under assault by a Lake Michigan we thought we knew but whose mercurial mood swings and true potential for devouring terrain we are only now beginning to understand.

Up and down the shore, anyone-a homeowner, business, public institution or municipality-with valuable lakefront property is caught in a web of uncertainty. For more than a decade the relentlessly rising lake has been swallowing beaches, pulverizing bluffs, undermining homes and pretty much frightening the daylights out of people. There has been a frantic scramble to take arms against a troublesome sea. Then suddenly this spring the lake turned kitten. The water level inexplicably dropped. Is it the beginning of a new cycle, everyone wonders, or just a momentary respite? Will it still be necessary, as many assume, to prepare for a renewed onslaught of rising water, which could spell disaster, or is it worth gambling that the lake has had its fun?